Calculating sunrise/sunset times

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To calculate sunrise and sunset times at a specific latitude and longitude, mathematical equations and algorithms can be utilized. The sunrise equation, as referenced, provides a method for determining the angle at which the sun rises or sets based on declination and latitude. Petter Duffett-Smith's book, "Practical Astronomy With Your Calculator," offers algorithms for these calculations, while Jean Meeus has also published several works on astronomical calculations. These resources can help in understanding the necessary formulas and methods for accurate time determination. Utilizing these references will enable effective calculation of sunrise and sunset times for any given day of the year.
ScienceMan
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I'm not sure if this is in the right forum but I assume someone in charge can move move it if it's not. Anyway, is there an equation or algorithm or something I can use to calculate the sunrise/sunset times at a given latitude/longitude on a given day of the year (or possibly something that would give me declination so I can put zero in and solve)? I know the basics of how it works (more extreme day lengths around the solstices and at higher latitudes and the sun not rising/setting at particularly high latitudes around the solstices, etc.) but I was wondering if there was a mathematical way to figure it out. I'm also aware that there are other things that go into it but I just need what I mentioned for my purposes.
 
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While this is going, I can give this equation which tells where ( angle ) the Sun rises ( or sets ), north or south of due East ( or west).
sin D = cos L sin ( ANGLE )
D= declination L=latitude
Now we have the when and where.
 
Petter Duffett-Smith wrote a book, Practical Astronomy With Your Calculator which includes algorithms for calculating sunrise and sunset, and many other astronomical events. A later version with co-author Jonathan Zwart includes instructions on using spreadsheets to calculate events. I used the former version several decades ago to write programs in Basic. It was entertaining then, archaic today, but the logic is the same.
 
Rob Saunders said:
Petter Duffett-Smith wrote a book, Practical Astronomy With Your Calculator

Or look up the works of Jean Meeus. He's written several books on astronomical calculation.
 
M 7.6 - 73 km ENE of Misawa, Japan https://earthquake.usgs.gov/earthquakes/eventpage/us6000rtdt/executive 2025-12-08 14:15:11 (UTC) 40.960°N 142.185°E 53.1 km depth It was however fairly deep (53.1 km depth) as compared to the Great Tohoku earthquake in which the sea floor was displaced. I don't believe a tsunami would be significant. https://earthquake.usgs.gov/earthquakes/eventpage/us6000rtdt/region-info

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